Today while I was routinely using my Macbook Pro 15" from early 2011 (model MacBookPro8,2), running Mavericks DP3, the screen suddenly went all glitchy and distorted and the system locked up. (I just mentioned the OS for the sake of completeness; I have a strong feeling that it's a hardware problem and has nothing to do with the OS.)

After forcing a reboot, I got the gray screen with the Apple logo and the spinner - except the display wasn't quite right: the entire screen was distorted by narrow white horizontal lines running across it. After a while the screen would transition to a purely gray one and the system would be nonresponsive (without ever having reached the login screen). After rebooting several times with the same result, I tried the different startup key sequences. I was able to reach single user mode (CMD + S) where I did fsck and the hard disk seemed to be OK. (FWIW, in text mode, the screen appeared normal.) exiting after the HD check didn't do any good though, and the system hung up again.

In the end what appeared to help was pressing the Shift + Control + Option + Power Button key combination (related to resetting the SMC) on the aforementioned pure gray screen, which would cause the system to instantly switch off. (Note that I did it while my system was already running, even though the procedure outlined by Apple requires that it be done while the computer is off.)

Upon turning on the laptop, the screen looked normal again, and the system booted as usual and I was able to log in. I was able to use my laptop normally for a couple of hours when suddenly the screen went completely red as I watching a video online. Force rebooting led to the same problems again, and I was able to "fix" it again, same as before - except this time round it only worked for a few minutes before the problem recurred (this time initiated by the screen turning a pure blue).

Since then I've only been able to use the system for a few minutes before the problem reoccurs.

Question is, how do I go about diagnosing the problem? (I suspect it might be a problem with the GPU or RAM.)

I couldn't get into Apple Hardware Test (AHT) even though I tried pressing D during startup. Apparently it's not there for systems running OS X 10.8.4 and above (I read that in one of the Apple docs although I don't have a reference to it this instant.)

Any help would be appreciated.

Edit: I should mention that the fix (i.e. the keyboard combination) doesn't always work the first time. I don't really know if pressing that particular combination actually helps at all - maybe it just randomly works after "turning it off and on again".

Update: I think the problem is related to the discrete graphics card (The AMD Radeon HD 6750M). I installed a free utility called gfxCardStatus that lets you know whether whether the integrated or discrete graphics chip is being used, and also lets you manually set it to one or the other. As soon as I set it to the discrete chip, the screen when all blue and liney on me, and after I force-rebooted I got all the symptoms of my problem.

The great thing about this little utility is that it lets me disable dynamic switching of the graphics chips and set the graphics to use the integrated chip. This means that my laptop should at least be usable until I'm able to get it fixed.

I'll be Googling on this issue later when I have time - a quick search showed that other people with the same MBP model as mine have also reported problems - but I'm still looking forward to suggestions here. Thanks!

Update 2: I think I was a bit hasty in pinning down the fault on the discrete graphics card. As I just found out, the problem can also be triggered when switching to the integrated graphics card, or may not be triggered at all by switching - I was able to switch between integrated and discrete without problems one time. I guess that the most that can be said right now is that the problem is with something in the graphics subsystem, and that it is possibly triggered by the switching from discrete to integrated graphics and vice versa.

Update 22nd Aug, 2013:

I took my MBP to an authorized service center where I live currently (in the Middle East) and they diagnosed the GPU as faulty, which is what I (and others here) had suspected. They said they would have to replace the logic board, which would cost the equivalent of over $1000 US. Doesn't seem to be worth it as I can buy an 11" version of the latest MacBook Air for slightly more.

Unfortunately, I'm no longer able to successfully apply my previous "trick" of force rebooting several times until the display comes up normal; it doesn't work anymore, after trying dozens and dozens of times. I just get the start-up chime, with the faulty display, followed by a blank gray screen.

If I boot up in Single User Mode (Command + S), the display begins to run normally, which I suppose is because it uses the integrated graphics card (just my guess). But that's the best I can manage; I'm no longer successful in getting it to boot so I can force the integrated card to be used (via the gfxCardStatus app).

  • Mate, I hope you did not sell your macbook before trying my solution !.. i had exactly the same problem but I could solve it just by replacing the battery.. Yes, the battery. Apparently when not plugged to current, the battery was not passing enough voltage to the logic board. Check my answer.
    – spacebiker
    Commented Jul 1, 2015 at 20:50
  • One way of diagnosing is seeing whther this reversible software procedure brings you any luck: apple.stackexchange.com/a/295805/251859 Commented Oct 16, 2017 at 16:56

7 Answers 7


Get the original DVD of your MacBook Pro, and boot it with the D key pressed. This will fire the Apple Hardware Test.

If you can have an hand on your system for enough time, open it to a remote access from another computer on your network (Ethernet or Wireless):

System Preferences > Sharing


Screen Sharing

Next time your display doesn't let you talk to your MacBook Pro, try to access it from your other computer and check that your MacBook Pro is up and running (this is my blind bet, please confirm ☺).

If it is running,

  • don't any more use the ^ ctrl⇧ shift⌥ alt while powering it off when your OS is up and running
  • rather make it remotely shutdown, wait 15 seconds, and then apply the above 4 simultaneous button press to reset the SMC.
  • Unfortunately, I don't have it anymore.
    – Aky
    Commented Jul 26, 2013 at 23:33
  • Could you tell which MBP model you exactly have: MacBookPro?,? (see System Profiler)?
    – dan
    Commented Jul 27, 2013 at 7:39
  • It's MacBookPro8,2
    – Aky
    Commented Jul 27, 2013 at 8:17
  • I think I may have narrowed down the problem to the graphics card, please check my updated question.
    – Aky
    Commented Jul 27, 2013 at 8:41
  • → Aky: place the MBP model in your OP, which is already a very good analysis.
    – dan
    Commented Jul 27, 2013 at 12:33

Apple has launched MacBook Pro Repair Extension Program for Video Issues which can be found here

Apple has determined that a small percentage of MacBook Pro systems may exhibit distorted video, no video, or unexpected system restarts. These MacBook Pro systems were sold between February 2011 and December 2013.

Apple or an Apple Authorized Service Provider will repair affected MacBook Pro systems, free of charge.

  • Thanks for this; even though I don't have the old MBP at hand anymore to be able to check out the serial number (it's in a different country), it's worth it if I were able to get it repaired for free to use as a backup laptop.
    – Aky
    Commented Feb 20, 2015 at 11:04
  • 1
    Thank you so much for this tip. I took my macbook to the apple store and they replaced the logic board, battery, and bottom at no charge because mine had failed the video test. This program has been extended to December 31, 2016.
    – prankin
    Commented Feb 24, 2016 at 19:07

Since your problem is intermittent! = Graphics card switching.

There is a little program called ColorSync Utility in your Utility folder.

Try it and use the Profile First Aid.

Also check if you have the suggested Firmware update here.

Computers that can be upgraded to use OS X Internet Recovery.

With new information (you narrowed it down to one of the graphics cards), now I wonder if it is your Mavericks not doing a good job in Graphics switching. I would in any case update the driver for the AMD graphics card.

  • The ColorSync Utility reported no problems, and my firmware version is the latest.
    – Aky
    Commented Jul 27, 2013 at 8:29
  • So it could be hardware problem, with things like the flat-band cable connecting the display to the logic board. Simple test would be to move your display to see if it happens. Or test it if you have external monitor, like using HDMI cable and plug it in to your TV :). Since you have DUAL graphics card wondering which one is it ?
    – Ruskes
    Commented Jul 27, 2013 at 8:35
  • 1
    I've got some new info and have updated the question. Definitely seems to be the graphics card.
    – Aky
    Commented Jul 27, 2013 at 8:40
  • I've updated the question again. I agree that the problem seems to be triggered by the graphics switching. I have been using Mavericks since it came out and have been on DP3 for at least a couple of weeks now, and yesterday is the first time the problem happened, so I don't know if it has anything to do with it. But I'll look into your suggestion to update the graphics drivers
    – Aky
    Commented Jul 27, 2013 at 10:06
  • Apparently I'll have to use BootCamp (which I don't really know anything about) to update to the latest drivers (if the one I have isn't already the latest). I don't really want to go down that route. Plus I'm assuming Apple's Software Update keeps the drivers updated to the right version depending on the system and the OS, so getting the "latest" one may not necessarily be the best thing.
    – Aky
    Commented Jul 27, 2013 at 10:23

I've been subjected to the same annoying problem with my MBP 15, running mavericks (newly updated)... and it seems the problem is Overheating in the HDD, and the only quick solution is to make the HDD get corrupt by itself with the peak heat it can reach after some time(NOT SAFE AT ALL), and to reboot (not the key combination which even I believed of). The heat actually spreads like a wildfire through the logic board... as Aky was living in Middle East, which is a hot place similar to my hot afternoon crashes,

I think I've got the solution... First, take care of the top left bottom corner of your MBP to not get hot... Or for a permanent help, replace your HDD with a SDD. pretty cheap than replacing logic board right?...

try this tip...

  • That wasn't my problem; besides the environment I use my laptop is fully air-conditioned. BTW, The HDD overheat problem that you seem to be experiencing often happens if the vents of your laptop get blocked with "dust bunnies"; perhaps you should have it opened up and cleaned out - might solve your issue (it's happened to several of my laptops over the years). Anyway, I got a new laptop now.
    – Aky
    Commented Mar 2, 2014 at 18:57

thi bis a very common issue amongst Macbook Pros late 2010, mainly early 2011 but also on occasional late 2011 MBP's. I believe it marks the start of Apple trying out new lead-free solder (is it the right term) causing quite an array of problems. the 6750M and another AMD card are often disabled. I also suffer from the WiFi card not working for the same reason. on another note the DVD player doesn't work either. It worked fine to get rid of drivers for the AMD discrete card in Mountain Lion, but then I made the error of installing Mavericks. The routines seem to have changed, so now I'm stuck with a computer that's pretty much disabled. Unfortunately Gfx Card Status seems to think I've got a second screen attached (this automatically activates the faulty 6750M discrete card). this prevents me from disabling the discrete graphics card. In system prefs you can sometimes disable the internal graphics card but not the "high performance" discrete one (energy saving prefs). I'm still to find a method to disable it.

There should be a way but my computer abilities are rudimentary, and scouring the web for solutions hasn't turned up more than endless testimonials without real solutions. If you strike gold finding a way to disable the discrete AMD 6750 on Mavericks I'd be ever so thankful to take part of it. [email protected] is my email address. There is a resoldering technique that could be of help (since the solder seems to be the cause for the most being) but that could of course push your computer over the edge completely. still, that's the best options I have left at this point. Sorry for not being able to be of more assistance! best of luck /Erik


There's a whole website and even a class-action lawsuit about this issue here:


See edit1:

This issue may happen on a faulty battery. My macbook complained for a long time to change the battery, it was almost death, but I tried to get the most of it. After one year, maybe longer, I got the same behavior as explained in the main question. I tried all kind of startup keys and at first I thought that was the solution because after trying so many times I could boot again successfully, but after a while it happened again. The laptop was getting very hot when not plugged to the current, this was freezing the macbook, sometimes i got the blue lines, other times it just got frozen and I could only hold the power button to reboot.

After some trial-error i realized the problem was happening because of a low voltage in the logic board. When plugged to the current everything worked like a charm, so next step for me is to get a battery replacement.

Hope this helps, cheers !

Edit 1:

After receiving the new battery the issue persists. Then i found this link https://www.apple.com/support/macbookpro..., apparently there is a known video issue for 15-inch and 17-inch MacBook Pro models manufactured in 2011 and 15-inch MacBook Pro with Retina models manufactured from Mid 2012 to Early 2013.

You can check in the link if your macbook is under the repair extension program and they would fix it for free. Mine does.

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